archive-1: SETI [ASTRO] New Investigation Questions The Distance, Cosmological
SETI [ASTRO] New Investigation Questions The Distance, Cosmological
Larry Klaes ( lklaes@bbn.com )
Fri, 22 Jan 1999 10:25:25 -0500
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>Date: Fri, 22 Jan 1999 4:53:39 GMT
>From: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
>To: astro@lists.mindspring.com
>Subject: [ASTRO] New Investigation Questions The Distance, Cosmological
Use Of Quasars
>Sender: owner-astro@brickbat12.mindspring.com
>Reply-To: Ron Baalke <BAALKE@kelvin.jpl.nasa.gov>
>
>University Communications Office
>University of California-San Diego
>
>Media Contact: Mario Aguilera, (619) 534-7572, mcaguilera@ucsd.edu
>
>FOR RELEASE: 10 a.m. CST, Wednesday, January 6, 1999
>
>NEW INVESTIGATION BY UCSD ASTRONOMER QUESTIONS
>THE DISTANCE, COSMOLOGICAL USE OF QUASARS
>
>Since they were discovered more than 35 years ago, science has
>largely accepted the idea that quasars -- since they are thought to
>be great distances from us -- could be used as cosmological tools
>to study the properties of the universe. Many astronomers have
>thought of quasars as windows to the history of our expanding
>universe.
>
>Striking new results announced today by Margaret Burbidge,
>university professor of astronomy in the Physics Department of the
>University of California, San Diego, show that these conventional
>views of quasars may not be correct.
>
>At this morning's session of the 193rd American Astronomical
>Society meeting in Austin, Texas, Burbidge will present data that
>suggest a group of quasars aligned in the sky with galaxy NGC 1068
>are much closer to Earth than previously believed. The study
>provides evidence that the quasars are in fact physically
>associated with NGC 1068 and it appears they have been ejected
>from the galaxy like cannonballs.
>
>"This paper provides evidence that quasars are not at great
>distances from us, and thus cannot be used for cosmological
>investigations," said Burbidge, a member of the Center for
>Astrophysics and Space Sciences at UCSD and a faculty member since
>1962.
>
>Using data from the Lick Observatory outside of San Jose, Burbidge
>studied the group of quasars aligned across and around NGC 1068, a
>bright galaxy relatively close at 30 million light years away.
>Traditional ideas in astronomy argued that each NGC 1068 quasar,
>because its observational spectra shifts strongly toward the red
>end of the spectrum, or "redshifts," must be far behind NGC 1068
>at varying distances. The clustering of quasars appeared to be an
>accident that we observe in our sky.
>
>Burbidge, to the contrary, argues that the clustering is no
>coincidence. Although the quasars do indeed have high redshifts,
>Burbidge's calculations say the quasars were ejected from the
>galaxy and remain near it. The complete study will be published in
>the Jan. 20, 1999 edition of The Astrophysical Journal Letters
>(volume 511).
>
>"If you count the number of quasars in the entire sky, you come up
>with about three per square degree," said Burbidge, who has
>studied the spectra of stars, galaxies and quasars for more than
>50 years. "But if you measure the area in NGC 1068, it averages to
>about 70 per square degree."
>
>Burbidge's study leaves open the question of the process that
>leads to the ejection of a quasar from a galaxy. And it casts
>doubt about the usefulness of strong redshift signals emanated by
>quasars.
>
>Nearly 70 years ago Edwin Hubble showed that the redshifts in the
>spectra of galaxies of stars were proportional to the distances of
>galaxies. This result, when interpreted in terms of Einstein's
>general theory of relativity, led to the belief that the universe
>is expanding.
>
>Shifts in spectrum lines suggest that objects are moving relative
>to the observer. Redshifts indicate objects are moving away from
>us, and the further away they are the faster they are moving.
>
>Since light travels to Earth at a finite speed, when we see an
>object with a large redshift, and that redshift is due to its
>distance away from us, we are looking back in time, seeing the
>object as it was when the light was emitted. Thus many believed
>that the large redshifts in some quasars could be used to study
>cosmology and to see the universe as it was billions of years ago.
>
>Burbidge's conclusions, while not arguing that all redshifts are
>not cosmological, question the value of using quasars to look at a
>younger universe because it now appears that all quasars are not
>at great distances from us.
>
>"There is no clear understanding of this within the framework of
>the physics that we currently understand," said Burbidge. "Thus
>once again astronomical observations are telling us something new
>about the physics of the universe."
>
>
>